SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7251803c0daabaef9857baf5529dc5fedf6892719a9d38f0feb42a879035b44e' 
  AND token = 'ntsw6KaWLsdxMcbtuzc0Qfklhx6Ag7dW3HwetZKrDfU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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