SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '094b73bef361407b7e6532955f9857b39aca8fc90c492f8a2e71d74ee8a5db83' 
  AND token = 'hsaMpFHJbsORjvdAnZoZyMz4Z/ibAGHxOPqO3gDSAMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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