SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e2d9ca10c35c72e30876510492f66ed27a8f2478cc9509057fcd9a1d5af344b5' 
  AND token = '+fV3y6uoFEDI5E2cRzCMY7sM3rbEzJKRiHs6QL0Y86w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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