SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b5cebfbfbfaec3576dc644e961dfee1ff6a1ff2703006efe6c4d02646598dc0' 
  AND token = '+dLp3xAFGGbq1itTcbgRZT16+G++aTT8d0IqDWkV628=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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