SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72e44147ac2b66f2eb67015df3726375ffeab2842736ad458870e70bb1e004ae' 
  AND token = '3K8qYIW7Od1rK1+qxlga4BnzTbjpO/a6mfsSPGAy4Ks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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