SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd0fcafda7a2240b34b11b92a43dd7d884c5ed37e24581b93d00fe49827b10170' 
  AND token = 'NU3lpsEt5ifaxcRvrClW6BEoXRdMd1U3F2o81VC93Fk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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