SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '432c7a14371576e07b37d764bf97714a2b7750b55c5bc4f7e27b84d410a83890' 
  AND token = 'L1u7jzcugNS5dwj9YJxBfhjAPBZ+drjcfQQqyRKvjNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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