SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f269a133e92d5d33324d865c9df55847d6241295186efd02d1013a5f831fda0' 
  AND token = 'zsvL+Yktu3XdmIM3HBVUQrokNq+jl4hcpMurgHNL61I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}