SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97f4ffefbe5bdbb37158562bc3da0e5499dea334f945c908dfdf01644746e58e' 
  AND token = '4VhHNVrgewFB0NQBJInoGZEx1SHxJPg0V3aV3eXOMXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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