SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'da80afe79651e9057cdf2a86f6278f3ffc9e0e7f7c617a3614bbb50a5120f90a' 
  AND token = 'uLrjWTQxDenxIsg1GV0WVN4+nBZ8xookXAy+6W3Nef0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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