SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bde325f3fccb93ee1389e65f7ec1aaecdf702bd380245888480a7538ad3b90dd' 
  AND token = 'ByxaxKVsIMsksVBow2BlXawuYKnR3LR/nsnuxIe7GB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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