SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11890267522b86a24f924192b91cf0237dd0ef51484f15fa5c2832b4fbe0ceda' 
  AND token = 'nWiMG6IDJfR6PjebGnZTA7+tJYvQ0dAk2Eapvcw8VLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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