SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd2b5426b9c2aa5535cf2a65b33e4dfd6faec4b81f362cb7bbdc90428805653f' 
  AND token = 'BUzoQwNJoqUs10e/RN+gRNgvWeLBifZOFYXnkrlIKL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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