SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b8985f30c2c3f8e465877c37ddec10906497d81a6b33b292b4d2771dd83f5f4c' 
  AND token = '5MNPbKz73odtCW/9hkSJDyznuw7lo1Ld+LZgaiQyFVM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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