SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9dae3d8f0318b69b0d01b33db97effa841d47b6556c292e032b361f410751f04' 
  AND token = 'fSUNk7g7GF2gKQu9gNXFmATgLxSLLwjSBOgtKWKfsTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}